Portable telephone



FIG. 1 is a front, top and left side perspective view showing our new design for a portable telephone;

FIG. 2 is a bottom plan view thereof in full lines;

FIG. 3 is a rear elevational view thereof in full line; and,

FIG. 4 is a right elevational view thereof in full lines. 

The ornamental design for a portable telephone, as shown and described. 